[Dietary calcium deprivation in the pregnant rat: evaluation of the repercussions on the maternal and fetal skeleton].

Authors have studied: calcemia, bone ashes calcium content and bone turnover by histofluorescence in 44 Wistar female adult rats. Control group (A) received for 21 days (equivalent to pregnancy) a normocalcemic diet, and group B an hypocalcemic diet. Both received demethyl-chlortetracycline intra-peritoneally at the beginning and end of the experience. Fetuses were fully calcinated and ash weight and calcium content determined. Group B shows a significative decrease in calcemia (F = 284.66, p less than 0.01), bone ash calcium content (F = 47.2, p less than 0.01) and an increase in endosteal bone resorption (F = 32.89, p less than 0.01), while bone formation including synthesis of bone matrix and calcium deposition is diminished (total bone formation, F = 20.0, p less than 0.01). No significative differences have been found among rats of the same group for the fact of being pregnant. No differences have been detected among fetuses of both groups. Fetuses seem to act as parasites and authors support a possible explanation for neonatal hypocalcemia.